TWI

An investigation was undertaken to evaluate friction stir processing (FSP) as a repair technique for AA 7075-T6 aluminium alloys and to examine the mechanical and fatigue performance of the repaired joints for applications such as repair of MIG and friction stir welded joints, porosity and reprocessing of existing weldments. Bead-on-plate trials were conducted on 7075 plates (thickness 12.7 mm) using a GTC Accu-Stir friction stir welding machine and tools with a concave shoulder and a truncated cone pin. Four FSP conditions were studied incorporating a single processed path at full penetration, reprocessing of a completely consolidated area and machining of artificial flaws. Repaired welds were subjected to phased array ultrasonic inspection and radiographic analysis and were characterised by metallography, tensile and fatigue tests.

12th International Symposium, 26-28 Jun 2018, Session 10B: FSP, Paper 02